<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    "use strict";
    // 单行
    /* 
    line1
    line2
    Alt+Shift+A
    */
    console.log('hello JS');
    console.log('hello CSS');
  </script>
</body>

</html>